You are installing a small drain for the end of the season draining of your swamp cooler on the roof you are at the rough plumbing stage can you glue a PVC reducer in to abs y vent line can't find abs?

don't know if its right but I've done it and had no problems. not a big deal either way usually plastic {at least schedule 40} can be friction fit and not leak as long as there is no water or gravity pressure on it.

ANS 2 - Use ABS/PVC Transition Cement for best results.